Rolling mills

ABSTRACT

A rolling mill stand is constituted by two pairs of housing posts, the rolls extending between the pairs of posts, and the posts of each pair defining between them a window for the roll chocks. For each pair of posts, there is a strap bridging the posts and interposed between the chocks and roll gap adjusting means. A beam is carried by the two straps and extends parallel to the roll axes to bridge the pairs of posts. This beam extends, at each end, beyond the housing posts and carries means for bending one of the rolls of the mill.

United States Patent Maltby [54] ROLLING MILLS [72] Inventor: Jack Maltby, Todwick, Sheffield, England [73] Assignee: Davy and United Engineering Company Limited, Sheffield, Yorkshire, England [22] Filed: Jan. 8, 1970 [21] Appl. N0.: 1,496

[58] Field of Search [4 1 June 6, 1972 [56] References Cited UNITED STATES PATENTS 3,364,715 H1 968 O'Brien ..72/245 3,373,588 3/1968 Stone ..72/237 Primary Examiner-Milton S. Mehr Attorney-Henry C. Westin [57] ABSTRACT A rolling mill stand is constituted by two pairs of housing posts, the rolls extending between the pairs of posts, and the posts of each pair defining between them a window for the roll chocks. For each pair of posts, there is a strap bridging the posts and interposed betweenthe checks and roll gap adjusting means. A beam is carried by the two straps and extends parallel to the roll axes to bridge the pairs of posts. This beam extends, at each end, beyond the housing posts and carries means for bending one of the rolls of the mill.

1 1 Claims, 4 Drawing Figures PATENTEBJUH 6 I972 3, 667. 272

SHEET 1 or a FIG. I

INVENTOR J MA L TBY HENRY c. WE 5T! N H/S ATTORNEY P'ATE'N'TEDJUM 6I972 3 667 272 SHEET 2 OF 3 INVENTOR j clr MALTBY ///s ATTORNEY ROLLING MILLS The present invention relates to rolling mills and is particularly concerned with the construction of a rolling mill stand, for example for rolling plate.

In U. S. Pat. No. 3,580,035 which issued on May 25, 1971 there is described a rolling mill stand including two pairs of housing posts, the members of each pair defining a space for roll chocks, a relatively massive base on which the housing posts are carried and a massive housing top which overlies the housing posts and which is adjustably displaceable vertically relative to the posts. As the size of rolling mill stands increases due to increased widths and thicknesses of material to be rolled it has been found increasingly more difficult to cast the base and housing top since their size is beyond the capacity of most suppliers of castings. Further even if it is possible to cast such massive castings, the overall weight of the stand is increased accordingly so that the foundations and other parts of the mill stand have to be strengthened to take up the increased load.

According to a first aspect of the present invention a rollingmill stand comprises two pairs of housing posts, the posts of each pair defining a space therebetween for receiving the roll chocks, a housing post strap arranged between the housing posts of each pair so as to be movable longitudinally of those posts, each strap being adapted to engage against the adjacent chock, roll gap adjustment means arranged to bear on each strap, a beam carried by the straps and extending substantially parallel to the roll axes beyond the pairs of housing posts at each end, and means carried by the ends of the beam for bending a roll of the mill.

According to a second aspect of the present invention, a rolling mill stand comprises two pairs of upstanding housing posts, the posts of each pair being spaced apart to define therebetween a window for the reception of roll chocks, the posts of each pair having lengthwise slots in the facing surfaces, for each pair a housing post strap received in the slots and bridging the posts of the pair, each strap being arranged to bear on the uppermost chock in the window, roll gap adjustment means carried jointly by the two straps, the beam bridging the pairs of housing posts and extending beyond the housing posts at each end, and means carried by the extended parts of the beam for bending the roll supported by the uppermost chock in each of the windows.

Preferably each pair of housing posts comprise the limbs of a U-shaped member. Each housing post may comprise two parts, a fixed part which is constituted by a limb of the U- shaped member and a detachable part. The slot may be provided in the detachable part, the slot extending longitudinally from the end which abuts the fixed part.

The roll gap adjustment means may comprise screwdown gear carried by the detachable part of each housing post and arranged to bear on the upper surface of the respective housing post strap.

The beam is preferably of a fabricated box-like construction rather than a one-piece casting thereby reducing the overall weight of the beam.

to each other by elongate members arranged between corresponding housing posts of each pair. The elongate members may be of fabricated box-like construction.

A second beam may be carried beneath the pairs of housing posts so as to extend beyond the planes through the pairs of housing posts and means may be carried by the extended parts for bending the roll supported by the lowermost chock in each of said spaces. The second beam is preferably of fabricated box-like construction.

The invention will be more readily understood by way of example, from the following description of a plate mill stand in accordance therewith, reference being made to the drawing accompanying the provisional specification, in which FIG. 1 is an end view of a four-high plate rolling mill stand, the left-hand half being shown in section,

FIG. 2 is a section on the line II-II of FIG. 1,

FIG. 3 is an end elevation of half the stand asviewed from III in FIG. 1 with a part of the drawing shown in section, and 7 FIG. 4 is a perspective view of the housing and other mill parts illustrated in the previous figures.

To facilitate the understanding of the drawings the left-hand portions of FIGS. 1 and 2 show the position of the rolls with the maximum roll gap between the work rolls and the righthand portions of FIGS. 1 and 2 and FIG. 3-show the position of the rolls when there is minimum gap between the work rolls.

The rolling mill stand 10 comprises two cast U-shaped housings 11, in each such housing, the two limbs constitute fixed parts of pairs of housing posts 13 andsare connected together by a tie 13A, as best shown in FIG. 4. Columns 14 which are attached by bolts 15 and nuts 16 to respective fixed parts of the housing posts 13 constitute detachable parts of the housing posts. The space between each pair of housing posts 13 forms a housing window 17 in which are located the back-up roll chocks 20, 21 and work roll chocks 22, 23. The upper work roll chock 22 is nested in the upper back-up chock 20 and the upper work roll 24 is maintainedin engagement with the upper back-up roll 26 by means of balance cylinders 28. The lower work roll chocks 23 are guided by means of guides 29 formed integrally with limbs of the housings 1 1. Each of the housings 11 is supported on foundations 30 by means of bed plates 31 so that the lower portion of each housing is located in a pit 32. The open end of each window 17 is closed by a housing post strap 36, the ends of which are located, in the slots 35 as shown in FIGS. 1, 2 and 4. Each strap 36 bears against its respective back-up roll. chock 20. Roll gap adjustment means including screwdown gear 38 is carried by each column 14 and is arranged to bear against the upper surface of the respective strap 36. Piston and cylinder units 39 are located in the limbs of the housings and are arranged so that they bear against the lower surfaces of the respective straps 36 thereby maintaining the straps 36 in engagement with the screws of the screwdown gear 38. Similarly hydraulic cylinders (not shown) in the guides 29 assist the back-up roll bending units 46 described hereinafter) to maintain the chocks 20 up against the straps 36.

The housings 11 are maintained at a fixed distance apart by means of elongate members 40 and 41. The members 40 are of box-like construction being fabricated from plate material whereas the members 41 are generally of l-section.

Back-up roll bending is applied to the necks 42-, 43 of the back-up rolls 26, 27 respectively outboard of the housings 1 1. In the case of the upper back-up roll 26, the roll bending apparatus comprises a fabricated beam 45 of box-like construction which is carried on the housing post straps 36. The beam 45 is located between the pairs of columns 14 and extends beyond the housings 11. Piston and cylinder units 46 are located in the ends of the beam 45. The piston of each unit 46 carries a bridle 48 which extends downwardly and to which two hooks 49 are pivotally attached. The hooks 49 engage shoulders 50 (FIG. 3) formed on outboard bearing chocks 51 which are pivotally attached to respective back-up chocks 20. By applying pressure to the piston and cylinder units 46, the bridles 48 are urged upwardly to cause the upper back-up roll 26 to bow and the chocks 51 to turn about pivots 52 (FIG. I). To facilitate the engagement and disengagement of the hooks 49 with the shoulders 50, ram units 53 (FIG. 3) are coupled between a downward extension 54 (FIG. 3) of the bridles 48 and a bracket 55 secured to each hook 49, whereby actuation of the ram units 53 will cause the hooks 49 to swing either towards or away from the shoulders 50.

In the case of the lower back-up roll 27, the roll bending apparatus comprises a beam of fabricated box-like construction arranged beneath the housings 11 and attached to the chocks 21, as will be described hereinafter. The ends of the beam 60 extend beyond the housings 1 l by the same extent as those of the upper beam 45. At each end of the beam 60, there is a bridle 62 which circumscribes the beamend and to which two hooks 63 are pivotally attached; these hooks 63 engage shoulders 64 formed on outboard bearing chocks 65, which are attached to the lower back-up roll chocks 21 by pivot pins 66. Piston and cylinder units 61 mounted on the beam 60 support the bridles 62 when roll changing. Hydraulic piston and cylinder units 68 of similar capacity as the units 46 are at- I tached to bridles 62 and engage the underside of the beam 60,

as shown in' FIG. 3. By applying pressure to the piston and cylinder units 68 the bridles 62 are urged downwardly to cause the lower back-up roll 27 to bow causing the chocks 65 to turn about the pivot pins 66. Ram units 67 are fitted between the bridle 62 and each hook 63 to facilitate the engagement and disengagement of the hooks 63 with the shoulders 64.

v For relatively small variation of the roll gap, as for example for automatic longitudinal gauge control, the lower back-up roll 27 is moved vertically relative to the housings l l by means of the hydraulic piston and cylinder units 70, of which the pistons 70A rest on the housings l 1 at the bottom of the windows 17 and the cylinders 70B are interposed between the pistons 70A and chocks 21. Each cylinder 70B is secured to a framework comprising a pair of plates 71 slidably mounted on opposite sides of the base 11A of the housing and secured together below base 11A by plate 72. The beam 60 is held in contact with pads 73 by spring bolts (not shown) between the beam 60 and plates 72.

The beam 60 is thussecured to the cylinders 70B and is therefore held at a constant separation from lower back-up roll chocks 21 regardless of the latters spacing from the housing bases 11A. As a result, the bending of back-up roll 27 produced by the units 68 is unaffected by roll gap changes effectedby the units 70; back-up roll bending and longitudinal gauge modulation are independent. I

Wheels 75- are provided on the lower work roll chocks 23 to facilitate work roll changing. When changing work rolls the lower work roll 25 is lowered by lowering the lower back-up roll 27 until the wheels engage roll change beams 76 arranged in the housing window 17. Then the upper work roll 24 is lowered by balance cylinders 28 and/or screwdown gear 38 until its chocks 22 rest on spacers (not shown) placed on the lower work roll chocks 23 and the work rolls 24, 25 are then ready after uncoupling the mill drives (not shown), to be run out of the mill stand 10. The lower back-up roll chocks 21 rest on sledges 77. Each sledge 77 has two pairs of wheels 78 which engage rollchange beams 79 when back-up roll chang' mg.

I claim:

1. A rolling mill stand comprising two pairs of housing posts, said pairs being spaced apart, a pair of'rolls;

roll chocks on said rolls slidingly located between the posts of each said pair;

' for each pair, a separate housing post strap bridging the posts of that pair, but movable lengthwise of said posts, said straps engaging against a different one of said chocks;

v roll gap adjustment means bearing on each said strap;

a beam carried jointly by said straps and extending substantiaily parallel to the roll axes, and between the posts of both said pairs; and

means carried by the ends of said beam for bending one of said rolls.

2. A rolling mill stand comprising:

two pairs of upstanding housing posts, said pairs being spaced apart;

a pair of rolls;

roll chocks on said rolls slidingly located between and guided by the posts of each said pair;

the posts of each pair having parallel lengthwise slots;

for each said pair, a separate housing post strap received in said slots and bridging the posts of that pair;

each said strap bearing on a different one of said chocks;

a roll gap adjustment means arranged to bear on each said strap;

a beam carried jointly by said two straps;

said beam bridging said pairs of housing posts and having projecting parts extending beyond the housing posts at each end; and

means carried by said projecting parts for bending said roll.

3. A rolling mill according to claim 2 in which each pair of housing posts comprise the limbs of a U-shaped member.

4. A rolling mill according to claim 3 in which each housing post comprises two parts, a fixed part constituted by a limb of said U-shaped member and a detachablepart secured to the upper extremity of the fixed part.

5. A rolling mill according to claim 4 in which the slot is formed in the detachable part of each housing post, the slot extending to the end abutting the fixed part.

6. A rolling mill according to claim 4 in which the roll gap adjustment means comprises screwdown gear carried by the detachable part of each housing and bearing against the upper surface of the respective housing post strap. I

7. A rolling mill according to claim 2 in which the beam is of fabricated box-like construction.

8. A rolling mill according to claim 2 in which the bending means comprise piston and cylinder units between said projecting parts of the beams and bearings on the roll outboard of the pairs of housing posts.

9. A rolling mill according to claim 2 in which there is a,

second beam located below the bottom chocks, bridging the pairs of housing posts and extending beyond the pairs of housing posts, second bending means being carried by the second beam for bending the adjacent roll.

10. A rolling mill according to claim 9 in which each pair of housing posts comprise the limbs of a U-shaped member, and in which the second beam is located below those U-shaped members.

11. A rolling mill according to claim 10 in which a hydraulic piston and cylinder unit is interposed between the bases of the U-shaped members and the bottom chocks in the windows, and said second beam is so carried as to move with those bottom chocks. 

1. A rolling mill stand comprisinG two pairs of housing posts, said pairs being spaced apart, a pair of rolls; roll chocks on said rolls slidingly located between the posts of each said pair; for each pair, a separate housing post strap bridging the posts of that pair, but movable lengthwise of said posts, said straps engaging against a different one of said chocks; roll gap adjustment means bearing on each said strap; a beam carried jointly by said straps and extending substantially parallel to the roll axes, and between the posts of both said pairs; and means carried by the ends of said beam for bending one of said rolls.
 2. A rolling mill stand comprising: two pairs of upstanding housing posts, said pairs being spaced apart; a pair of rolls; roll chocks on said rolls slidingly located between and guided by the posts of each said pair; the posts of each pair having parallel lengthwise slots; for each said pair, a separate housing post strap received in said slots and bridging the posts of that pair; each said strap bearing on a different one of said chocks; a roll gap adjustment means arranged to bear on each said strap; a beam carried jointly by said two straps; said beam bridging said pairs of housing posts and having projecting parts extending beyond the housing posts at each end; and means carried by said projecting parts for bending said roll.
 3. A rolling mill according to claim 2 in which each pair of housing posts comprise the limbs of a U-shaped member.
 4. A rolling mill according to claim 3 in which each housing post comprises two parts, a fixed part constituted by a limb of said U-shaped member and a detachable part secured to the upper extremity of the fixed part.
 5. A rolling mill according to claim 4 in which the slot is formed in the detachable part of each housing post, the slot extending to the end abutting the fixed part.
 6. A rolling mill according to claim 4 in which the roll gap adjustment means comprises screwdown gear carried by the detachable part of each housing and bearing against the upper surface of the respective housing post strap.
 7. A rolling mill according to claim 2 in which the beam is of fabricated box-like construction.
 8. A rolling mill according to claim 2 in which the bending means comprise piston and cylinder units between said projecting parts of the beams and bearings on the roll outboard of the pairs of housing posts.
 9. A rolling mill according to claim 2 in which there is a second beam located below the bottom chocks, bridging the pairs of housing posts and extending beyond the pairs of housing posts, second bending means being carried by the second beam for bending the adjacent roll.
 10. A rolling mill according to claim 9 in which each pair of housing posts comprise the limbs of a U-shaped member, and in which the second beam is located below those U-shaped members.
 11. A rolling mill according to claim 10 in which a hydraulic piston and cylinder unit is interposed between the bases of the U-shaped members and the bottom chocks in the windows, and said second beam is so carried as to move with those bottom chocks. 